Hydraulic door closer



United States Patent 3,259,937 HYDRAULIC DOOR CLOSER Nicholas Kotikov,3132 Unruh Ave., Philadelphia 49, Pa. Filed Sept. 30, 1963, Ser. No.312,475 Claims. (CI. 16-51) The present invention relates to a hydraulicdoor closer and it consists in the combinations, constructions andarrangement of parts hereinafter described and claimed,

A door closing device that makes use of compressing air within it forslowing down the closing movement of the door has the disadvantage thatair is compressible and therefore the door will first be rapidly swungtoward closed position by the device and then at the very end of theclosing movement, the air in the device will be compressed sutlicientlyto slow up the final closing of the door. Often the door bounces backbefore closing. Hydraulic fluid has the advantage over air in that it isnot compressible like air and therefore a door closer using hydraulicfluid will slow down the closing movement of the door from the verybeginning. The drawback of using hydraulic door closers of theconventional type is that the hydraulic fluid will leak out during theoperation of the device and the door closer finally runs dry.

The conventional hydraulic fluid door closer makes use of a piston rodthat slides through a packing gland at the end of the cylinder. Everytime the rod is partially pulled out of the cylinder during the openingmovement of the door, a very fine film of fluid remains on the rod andthe packing gland prevents this fluid film from being returned to theinterior of the cylinder. In time the fluid in the device finally runsdry. Even when the piston rod is highly polished, a thin film of fluidwill still be applied to the rod and the fluid will leak out of thedevice.

The principal object of my invention is to provide a hydraulic doorcloser in which the hydraulic fluid is contained in compartments thatwill vary in capacity during the opening and closing movement of theparts due to the opening and closing of the door to which the device isattached, but the compartments will contain all of the fluid at alltimes and permit none of it to escape. The device therefore cannot rundry through use.

A further object of my invention is to provide a hydraulic door closerthat is simple in construction and is durable and efficient for thepurpose intended.

Other objects and advantages will appear as the specification continues.The novel features of the invention will be set forth in the appendedclaims.

Drawing For a better understanding of my invention, reference should bemade to the accompanying drawing, forming part of this specification, inwhich:

FIGURE 1 is a longitudinal section through the hydraulic door closer.

FIGURE 2 is a longitudinal section on a smaller scale showing the devicein closed position, certain parts of the device being shown inelevation.

FIGURE 3 is a longitudinal section on the same scale as FIGURE 2 andshows the device in open position, certain parts of the device beingshown in elevation.

FIGURE 4 is a transverse section taken along the line 44 of FIGURE 1 andshows the device on the same scale as FIGURE 1.

FIGURE 5 is a view showing the hydraulic door closer attached to a doorand door frame and shows the device and door in closed position in fulllines and in open position in dot-dash lines.

While I have shown only the preferred form of my invention, it should beunderstood that various changes, or modifications, may be made withinthe scope of the annexed claims without departing from the spiritthereof.

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Detailed description In carrying out my invention I provide a hydraulicdoor closer which comprises an outer cylinder A. Within the outercylinder I slidably mount an inner cylinder B. The outer cylinder A hasa front bearing 1 and this hearing has an opening 2 for slidablyreceiving the inner cylinder B. The outer cylinder A has an inwardlycurved flange 3 that receives the front bearing 1.

The opposite end of the outer cylinder A is closed by a header C. Thisheader has an annular recess 4 in its outer surface for receiving theinwardly crimped end 5 of the outer cylinder A. In this way the header Cis secured to the outer cylinder.

Again referring to the inner cylinder, it will be seen that the righthand end is provided with a bearing sleeve D. This bearing sleeve has anannular flange 6 whose outer periphery rides on the inner surface of theouter cylinder A. The bearing sleeve D also has a cylindrical portion 7that extends into the interior of the inner cylinder B. The cylindricalportion 7 has an outer annular groove 8 for receiving the inwardlycrimped right hand end 9 of the inner cylinder B. An 0 ring 10 isreceived in an annular groove in the cylindrical portion 7 and bearsagainst the inner surface of the inner cylinder B for forming afluid-tight joint.

It will be seen from FIGURE 1, that I mount a hollow central piston rodE within the outer cylinder A and this rod extends through a centralbore 11 in the bearing sleeve D and projects into the interior of theinner cylinder B. The right hand end of the hollow piston rod E isreceived in a central bore 12 provided in the header C. The cylindricalportion 13 of the header C that has the bore 12 therein, has its outerend crimped inwardly as shown at 14 for forming an inwardly extendingannular rib 15 in the hollow piston rod E for staking of the rod in theheader C.

The left hand end of the hollow piston rod E is received in a bore 16provided in a cylindrical portion 17 of a piston F. The piston has anoutwardly extending flange 18 whose outer periphery is formed into apolygon. The polygonal periphery provides spaces 19 for the passage offluid from one side of the piston to the other side, see'FIGURES 2 and3.

The piston F has a cylindrical portion 20 for receiving a piston cup Gpreferably made of rubber or Neoprene. The cylindrical portion 20 isprovided with an annular groove 21 for receiving the inner cylindricalportion of the piston cup G. The center cylindrical portion of thepiston cup will have its outer edge bearing against the shoulder formingone side of the annular groove 21 and this shoulder will hold the cup inplace on the piston F. The piston cup G has a long and thin outer lipthat rides over the inner surface of the inner cylinder B. This thinannular lip collapses during the opening movement of the door ashereinafter explained and permits the fluid to flow from the right handside of the piston to the left hand side.

I provide a coil spring H and mount this between the outer and innercylinders A and B. The left hand end of the coil spring H bears againstthe front bearing 1 while the right hand end bears against the flange 6of the bearing sleeve D. The coil spring H yieldingly moves the innercylinder B into the outer cylinder A. FIGURE 1, shows the device in aclosed door position and the inner cylinder is shown entirely receivedwithin the outer cylinder except for the left hand end of the innercylinder that projects beyond the front bearing 1.

The left hand end of the inner cylinder B is secured to a front plug J.The plug I has an annular groove and an O ring 22 is placed in thegroove so as to seal the left hand end of the inner cylinder and preventfluid leaking from the inner cylinder B and past the plug J. The plug Jis provided with an opening 23 by means of which the i in turn issecured to a door frame L.

One of the principal features of my invention is to a provide means forhousing the fluid within the hydraulic door closer and sealing thisfluid from escaping to the atmosphere. In other words, the fluid withinthe device is prevented from leaking out during the operation of thedoor closer. and therefore the door closer will not run dry through use.passage for the hydraulic fluid which will still permit .the door closerto operate. 7 a

In FIGURE 1, I show the bearing sleeve D provided with an annular flange24. A flexible bellows M has a convolution 25 in its left hand endformedfor receiving the annular flange 24 on the bearing sleeve D. A wrapping26 is received in the annular groove provided at the left hand end ofthe bellows M and this wrapping secures the left hand end of the bellowsto the bearing sleeve D and makes a fluid-tight connection. tral bore 11in the bearing sleeve D has a diameter larger than the outer diameter ofthehollow piston rod E and this will permit fluid to pass from one sideof the'bean'ng sleeve D to the other side.

The cen- To accomplish this, I provide a closed The right hand end ofthe flexible bellows M is secured I to the head C to form theliquid-tight seal therewith'in the same manner as the left hand end issecured to the bearing sleeve D. The header C has an annular flange 27for entering a right hand convolution 28 provided in the bellows M andadjacent to the right hand end of the bellows. A wrapping 29 is receivedin an annular groove 30 in the bellows M and secures the right hand endofthe bellows to the header C for making a liquidtight joint. 1

Acompartment Q is provided by the bellows M, the bearing sleeve D andthe header C. The compartment Q is in communication with the compartmentP by means of the enlarged central bore 11 in the bearing sleeve D. Thecompartment Q also is in communication with passages 31 provided in theheader C. FIGURE 1 shows the passages 31 communicating with the centralbore 12 and this bore in turn communicates with the interior'of thehollow piston rod E that leads to the compartment R. The bore 12 has anannular shoulder 33 against which the end of the piston rod E bears. Anadjusting screw S has its inner end adapted to regulate the amount offluid flowing from the passage 12 into the passages 31. The adjustingscrew is received .in a threaded bore 37 provide in the header C. Thisflow takes place during the closing of the door as will be hereinafterexplained. The adjusting screw S can be manually adjusted to controlthe'speed at which the door will close. An 0 ring seals the adjustingscrew S so that no fluid can leak thereby.

The compartments P, Q and R will contain the hydraulic fluid whether thedoor is opened or closed. As the door opens, the inner cylinder B willhave its left hand end extended from the outer cylinder A, see FIGURE 3,but there will be no film of fluid on the outer surface of the exposedportion of the inner cylinder because at no time does the hydraulicfluid contact the outer surface of the inner cylinder.

When the door closure is in closed position as shown in FIGURE 2, thebellows M will be compressed and the coil spring H will be expanded.When the door N is opened, the inner cylinder B will be extended fromthe outer cylinder A as shown in FIGURE 5, and the flange 6 on thebearing sleeve D will move the right hand end of the coil spring H so asto compress the spring. ;This movement of the bearing sleeve D willexpand the bellows M, but there will be no leakage of the fluid into theinterior of, the outer cylinder A. During the'movement of the bearingsleeve D to the left in FIGURE 3, the fluid housed within thecompartment P and formed by the inner cylinder B, the outer surface ofthe hollow piston rod E, the piston F and the bearing sleeve D will beforced past the piston cup G and the thin outer wall of the cup willcollapse and permit the fluid to enter the compartment R as thecompartment P is reduced in capacity. The compartment R is formed by theinner cylinder B, the front plug J and the piston F withits piston cupG. The compartment R will be increased in capacity as the compartment Pis reduced in capacity.

. However, when the door is released for closing it and the coil springH tends to move the outer cylinder A so as to telescope it over theinner cylinder B, the hollow piston rod E will be moved as a unit withthe outer cylinder because the two are interconnected by the header C.This will tend to cause the. piston Fto move tothe left within the innercylinder B, see FIGURE ;3, and to decrease the, capacity of the fluidcompartment R. Some of the fluid inthis compartment will therefore beforced through the-interior of the hollow piston rod E and will flowinto the passage 12 and will endeavor to enter the passages 31. The.extent that the inner end, of the adjusting screw opens communicationbetween the passage 12 and the passages 31 controls the amount of fluidentering the passages 31 and how quickly the door will be closed by thespring H. In this way a controlled opening for the flow of fluid fromthe fluid compartment R, through the interior of the hollow piston-rod Eand thence through the bore 12 and the passages 31 and to thecompartment Q is provided.

It 'Will be seen from the foregoing description that the fluid is alwayscontained Within the three fluid compart- .ments P, Q, and R regardlessof whether the door is Also it will be seen that no fluidcan contactwith the outer surface of the inner cylinder B closed or open.

are spaced circumferentiallyapart and are shaped like.

the protuberances 40. The outer protuberances 40 will ride on the innersurface of the outer cylinder A before the outer loops of the bellows Mcontacts with this surface at any point during the expanding andcontracting of the bellows. This will take place on the outer loops ofthe bellows. The inner protuberances 41 will ride on the outer surfaceof the hollow piston rod E before the inner loops of the bellows Mcontacts with this surface at any point during the expanding andcontracting of the bellows. This will prevent wear taking place on theinner loops of the bellows.

In FIGURE 1, the two ends, of the .bellows M are shown in section. theseends is also in section but the drawing indicates this portion by a'singe line formed into a series of inner and outer loops rather'thanadouble .pair of lines in parallel arrangement and following .the samecontour. The complete showing of a sectioned bellows M in FIG- URE 1from end to end of the bellows would make the drawing more difficult tounderstand since the scale is so small. The scale of FIGURES 2 and .3 istoo small to indicate .the outer protuberances 40 and they are not il-.lustrated in these two figures.

No ball check valve in the passage 12 in the header C 'is necessary ifthe piston cup G has a tapered outer lip that is thin enough to collapseand permit the fluid to flow directly from the compartment P into thecompartment R during the opening of the door and the movethat cannotcollapse to permit fluid to pass thereby during The inner loops of theconvolutions are The portion of the bellows between the opening movementof the door, then a ball check valve, not shown, in the passage 12 wouldbe needed.

I claim:

1. A hydraulic door closer comprising:

(a) an outer elongated cylinder open at one end;

(b) an inner cylinder slidably mounted in said open end and having itsinner end extending into said outer cylinder; said inner cylinder beingmovable to have a portion project from the outer cylinder;

(c) a bearing sleeve slidably mounted in said outer cylinder and havingthe inner end of said inner cylinder hermetically sealed thereto;

(d) a header closing the opposite end of said outer cylinder and havinga central bore;

(e) a hollow piston rod having one end secured to said header, theinterior of said piston rod communicating with the central bore in saidheader;

(f) said bearing sleeve having a central opening for receiving saidhollow piston rod and being of a larger diameter than the outer diameterof said piston rod;

(-g) a piston mounted on the end of said hollow piston rod that isdisposed opposite to the end connected to said header, said pistonhaving a central opening communicating with the interior of said hollowpiston rod;

(h) a coil spring disposed between said outer and inner cylinders andbearing against said bearing sleeve for yieldingly urging said sleevetoward said header for moving said inner cylinder within said outercylinder;

(i) a flexible bellows enclosing said hollow piston rod and having oneend hermetically sealed to said hearing sleeve so as to enclose thecentral opening in said sleeve and having its other end hermeticallysealed to said header;

(j) said header having a valve-controlled fluid passage opening into afirst fluid receiving compartment bounded by said bellows, bearingsleeve, the exterior surface of said hollow piston, and said header,said fluid passage also communicating with the central bore in saidheader;

(k) a second fluid-receiving compartment bounded by the inner surface ofsaid inner cylinder and the outer surface of said hollow piston rod andby said piston and by said bearing sleeve, the second compartment beingin communication with said first-named compartment by the central borein said bearing sleeve;

(1) a third fluid-receiving compartment bounded by the inner surface ofsaid inner cylinder and by said piston and by a plug hermeticallysealing the outer end of said inner cylinder; said third compartmentbeing in communication with the interior of said hollow piston rod; and

(m) said three compartments being filled with fluid and beinghermetically sealed for preventing the escape of fluid and forpreventing any fluid from contacting with the outer surface of saidinner cylinder; whereby no film of fluid will collect on the portion ofthe outer surface of said inner cylinder that is extendible from saidouter cylinder.

2. The combination as set forth in claim 1: and in which (a) saidbellows has outwardly extending looped portions provided with outwardlyextending projections that will prevent said outwardly looped portionsfrom contacting with the inner surface of said outer cylinder; and

(b) said bellows has inwardly extending looped portions provided withinwardly extending projections that will prevent said inwardly loopedportions from contacting with the outer surface of said hollow pistonrod.

3. In a hydraulic door closer;

(a) an outer cylinder having an open end;

(b) an inner cylinder slidable in said open end and extending into saidouter cylinder; said inner cylinder being movable to have a portionproject from the outer cylinder;

(0) a bearing sleeve slidable in said outer cylinder and having theinner end of said inner cylinder hermetically sealed thereto;

(d) a header closing the outer cylinder at the end opposite said openend;

(e) a hollow piston rod having one end secured to said header andextending through a central bore in said bearing sleeve;

(f) a bellows enclosing the portion of said hollow piston rod disposedbetween said bearing sleeve and said header and having one endhermetically sealed to said bearing sleeve so as to enclose the centralbore therein and having its other end hermetically sealed to saidheader;

(g) said header having valve-controlled passages placing the interior ofsaid hollow piston rod in communication with the interior of saidbellows;

(h) a piston mounted on the free end of said hollow piston rod and beingslidably mounted in said inner cylinder, said piston having a centralbore communicating with the interior of said hollow piston rod;

(i) a plug hermetically sealing the outer end of said inner cylinder;and

(j) a fluid filling the inner cylinder on both sides of said piston andfilling the interior of said bellows and the interior of said hollowpiston rod; said bellows preventing the fluid from escaping to the outersurface of said inner cylinder.

4. The combination as set forth in claim 3: and in which which (a) saidbellows will elongate during the movement of said bearing sleeve towardsaid piston and will still have its ends hermteically sealed to saidbearing sleeve and said header so as to prevent any leakage of fluidinto the interior of said outer cylinder.

References Cited by the Examiner UNITED STATES PATENTS 6/1939 Binder eta1. 2678 3/ 1943 Katcher.

10/ 1946 Magrum.

1/ 1 Montgomery. 4/ 1953 Mercier 2678 9/ 1954 Roussel 1652 2/1956Schultze 2678 FOREIGN PATENTS 7/1953 Great Britain.

PATRICK A. CLIFFORD, Primary Examiner.

DONLEY I. STOCKING, JOSEPH D. SEERS,

Examiners.

I. G. GILFILLAN, J. H. MCGLYNN,

Assistant Examiners.

1. A HYDRAULIC DOOR CLOSER COMPRISING: (A) AN OUTER ELONGATED CYLINDEROPEN AT ONE END; (B) AN INNER CYLINDER SLIDABLY MOUNTED IN SAID OPEN ENDAND HAVING ITS INNER END EXTENDING INTO SAID OUTER CYLINDER; SAID INNERCYLINDER BEING MOVABLE TO HAVE A PORTION PROJECT FROM THE OUTERCYLINDER; (C) A BEARING SLEEVE SLIDABLY MOUNTED IN SAID INNERCYLINCYLINDER AND HAVING THE INNER END OF SAID INNER CYLINDERHERMETICALLY SEALED THERETO; (D) A HEADER CLOSING THE OPPOSITE END OFSAID OUTER CYLINDER AND HAVING A CENTRAL BORE; (E) A HOLLOW PISTON RODHAVING ONE END SECURED TO SAID HEADER, THE INTERIOR OF SAID PISTON RODCOMMUNICATING WITH THE CENTRAL BORE IN SAID HEADER; (F) SAID BEARINGSLEEVE HAVING A CENTRAL OPENING FOR RECEIVING SAID HOLLOW PISTON ROD ANDBEING OF A LARGER DIAMETER THAN THE OUTER DIAMETER OF SAID PISTON ROD;(G) A PISTON MOUNTED ON THE END OF SAID HOLLOW PISTON ROD THAT ISDISPOSED OPPOSITE TO THE END CONNECTED TO SAID HEADER, SAID PISTONHAVING A CENTRAL OPENING COMMUNICATING WITH THE INTERIOR OF SAID HOLLOWPISTON ROD; (H) A COIL SPRING DISPOSED BETWEEN SAID OUTER AND INNERCYLINDERS AND BEARING AGAINST SAID BEARING SLEEVE FOR YIELDINGLY URGINGSAID SLEEVE TOWARD SAID HEADER FOR MOVING SAID INNER CYLINDER WITHINSAID OUTER CYLINDER; (I) A FLEXIBLE BELLOWS ENCLOSING SAID HOLLOW PISTONROD AND HAVING ONE END HERMETICALLY SEALED TO SAID BEARING SLEEVE SO ASTO ENCLOSE THE CENTRAL OPENING IN SAID